{"nhtsa_id":631808,"type":"service_bulletin","type_name":"Service bulletin","date_added":"2002-06-20","date":"2001-12-01","document_id":"25WT00A","mfr_campaign":null,"replaces":"25WT00","component":"POWER TRAIN:MANUAL TRANSMISSION","mfr_system":null,"summary":"SUBJECT REGARDING SUMP COOLING AND DIRECT MOUNT COOLING PROVISION FOR HD/B 500 RETARDER EQUIPPED TRANSMISSIONS, HD 4000/B 500. *SLC","document":null,"url":"https://open.wenmarpro.com/bulletins/631808","components":[{"id":"powertrain","name":"Transmission and driveline","parent":null},{"id":"manual-transmission","name":"Manual transmission","parent":"powertrain"}],"codes":[],"topics":[],"vehicles":[{"make":"GMC","model":"GM","year_from":null,"year_to":null,"match":null,"vehicle_ids":[]}],"as_of":"2026-10-19","note":"A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.","attribution":[]}